Written procedures should monitor progress and control performance of steps that cause variability in quality characteristics, with in-process controls and acceptance criteria set from development or historical data; the type and extent of testing may vary with the material, the step and how much variability it introduces, with looser controls early and tighter ones at isolation and purification. The critical in-process controls and critical monitoring, with their control points and methods, should be written down and carry quality unit approval. Qualified production staff may perform in-process controls and adjust the process without prior quality approval if adjustments stay inside limits the quality unit approved, with all tests and results fully documented in the batch record. Written procedures should describe scientifically sound sampling methods and plans for intermediates, APIs and material mid-process, designed to avoid contaminating the sample or other materials and to keep samples intact after collection. An OOS investigation is not normally expected for an in-process test run only to monitor or adjust the process.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.